Ultra wideband (UWB) impulse radar systems utilize pulse widths on the order of hundreds of picoseconds (trillionth of a second). Because such short pulses necessarily have very few cycles or even a single cycle of RF signal (such as a Gaussian monopulse), UWB radars may be considered to operate in the time domain as opposed to conventional frequency domain processing of received pulses. This time domain operation enables UWB radars to enjoy very fine range resolutions such as on the order of a fraction of a few feet or less. In addition, UWB radars have high power efficiency because of their low transmit duty cycle. Moreover, UWB radars provide users with a very low probability of detection because their transmitted pulses occupy a relatively large bandwidth and thus have low power spectral density.
Given their advantages, a great deal of research and development has been dedicated to the subject of UWB radars. For example, see-through-wall UWB radars have been developed that enable users to detect targets such as people on the other side of walls and floors. Such UWB radars are naturally of great interest to military and law enforcement agencies. However, their current range resolution is rather coarse. Moreover, a user typically must physically move the see-through-wall radar to image the contents behind the wall.
Accordingly, there is a need in the art for UWB radars with enhanced range resolution and scanning capabilities.